﻿#region File and License Information
/*
<File>
	<License Type="BSD">
		Copyright © 2009 - 2012, Outcoder. All rights reserved.
	
		This file is part of Calcium (http://calciumsdk.net).

		Redistribution and use in source and binary forms, with or without
		modification, are permitted provided that the following conditions are met:
			* Redistributions of source code must retain the above copyright
			  notice, this list of conditions and the following disclaimer.
			* Redistributions in binary form must reproduce the above copyright
			  notice, this list of conditions and the following disclaimer in the
			  documentation and/or other materials provided with the distribution.
			* Neither the name of the <organization> nor the
			  names of its contributors may be used to endorse or promote products
			  derived from this software without specific prior written permission.

		THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
		ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
		WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
		DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
		DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
		(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
		LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
		ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
		(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
		SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	</License>
	<Owner Name="Daniel Vaughan" Email="danielvaughan@outcoder.com"/>
	<CreationDate>2010-10-21 15:34:42Z</CreationDate>
</File>
*/
#endregion

using System.Windows.Input;
using Outcoder.CommandModel;

#if NETFX_CORE
using Windows.UI.Xaml;
#else
using System;
using System.Reflection;
using System.Windows;
using System.Windows.Data;
#endif

namespace Outcoder.UI.Xaml
{
	/* TODO: [DV] Comment. */
	public static class Commanding
	{
		#region Command Property

		public static DependencyProperty CommandProperty
			= DependencyProperty.RegisterAttached(
				"Command",
				typeof(ICommand),
				typeof(Commanding),
#if NETFX_CORE
				new PropertyMetadata(null, HandleCommandChanged));
#else
				new PropertyMetadata(HandleCommandChanged));
#endif

		public static void SetCommand(DependencyObject obj, ICommand propertyValue)
		{
			obj.SetValue(CommandProperty, propertyValue);
		}

		public static ICommand GetCommand(DependencyObject obj)
		{
			return (ICommand)obj.GetValue(CommandProperty);
		}

#if WINDOWS_PHONE
		const string defaultEventName = "Tap";
#else
		const string defaultEventName = "Click";
#endif
		static void HandleCommandChanged(
			DependencyObject d, DependencyPropertyChangedEventArgs e)
		{
			CommandAttachment attachment = GetBehavior(d);
			var command = e.NewValue as ICommand;
			attachment.Command = command;
			if (command != null && string.IsNullOrEmpty(attachment.EventName))
			{
				var eventCommand = e.NewValue as IEventCommand;
				string eventName = eventCommand != null
							&& !string.IsNullOrEmpty(eventCommand.EventName)
								? eventCommand.EventName : defaultEventName;
				attachment.EventName = eventName;
			}

			var element = d as FrameworkElement;
			if (element != null)
			{
				element.Unloaded -= HandleAssociatedObjectUnloaded;
				element.Unloaded += HandleAssociatedObjectUnloaded;
				element.Loaded -= HandleAssociatedObjectLoaded;
				element.Loaded += HandleAssociatedObjectLoaded;
			}
		}

		static void HandleAssociatedObjectUnloaded(object sender, RoutedEventArgs args)
		{
			CommandAttachment attachment = GetBehavior((DependencyObject)sender);
			Detach(attachment);
		}

		static void Detach(CommandAttachment attachment)
		{
			attachment.Detach();
		}

		static void HandleAssociatedObjectLoaded(object sender, RoutedEventArgs e)
		{
			var d = (DependencyObject)sender;
			CommandAttachment attachment = GetBehavior(d);
			Attach(d, attachment);
		}

		static void Attach(DependencyObject d, CommandAttachment attachment)
		{
			attachment.Detach();
			attachment.Attach(d);
			attachment.Command = GetCommand(d);
			string eventName = GetEvent(d);
			if (string.IsNullOrWhiteSpace(eventName))
			{
				eventName = defaultEventName;
			}
			attachment.EventName = eventName;
			attachment.CommandParameter = GetCommandParameter(d);
		}

		#endregion

		#region Command Parameter

		public static readonly DependencyProperty CommandParameterProperty
			= DependencyProperty.RegisterAttached(
				"CommandParameter",
				typeof(object),
				typeof(Commanding),
#if NETFX_CORE
				new PropertyMetadata(null, HandleCommandParameterChanged));
#else
				new PropertyMetadata(HandleCommandParameterChanged));
#endif
		static void HandleCommandParameterChanged(
			DependencyObject d, DependencyPropertyChangedEventArgs e)
		{
			CommandAttachment attachment = GetBehavior(d);
			attachment.CommandParameter = e.NewValue;
		}

		public static void SetCommandParameter(
			DependencyObject obj, object propertyValue)
		{
			obj.SetValue(CommandParameterProperty, propertyValue);
		}

		public static object GetCommandParameter(DependencyObject obj)
		{
			return obj.GetValue(CommandParameterProperty);
		}

		#endregion

		#region Event Property

		public static DependencyProperty EventProperty
			= DependencyProperty.RegisterAttached(
				"Event",
				typeof(string),
				typeof(Commanding),
				#if NETFX_CORE
				new PropertyMetadata(null, HandleEventChanged));
#else
				new PropertyMetadata(HandleEventChanged));
#endif

		public static void SetEvent(DependencyObject obj, string propertyValue)
		{
			obj.SetValue(EventProperty, propertyValue);
		}

		public static string GetEvent(DependencyObject obj)
		{
			return (string)obj.GetValue(EventProperty);
		}

		static void HandleEventChanged(
			DependencyObject d, DependencyPropertyChangedEventArgs e)
		{
			CommandAttachment attachment = GetBehavior(d);
			var eventName = e.NewValue as string;
			attachment.EventName = eventName;
		}

		#endregion

		#region CommandBehavior Property

		static readonly DependencyProperty CommandBehaviorProperty
			= DependencyProperty.RegisterAttached(
				"CommandBehavior",
				typeof(CommandAttachment),
				typeof(Commanding),
				null);

		static CommandAttachment GetBehavior(DependencyObject d)
		{
			var attachment = (CommandAttachment)d.GetValue(CommandBehaviorProperty);

			if (attachment == null)
			{
				attachment = new CommandAttachment(d);
				d.SetValue(CommandBehaviorProperty, attachment);
			}

			return attachment;
		}

		#endregion

// Experimental
//#if SILVERLIGHT
//		#region CommandPath Property
//
//		public static DependencyProperty CommandPathProperty
//			= DependencyProperty.RegisterAttached(
//				"CommandPath",
//				typeof(string),
//				typeof(Commanding),
//				new PropertyMetadata(HandleCommandPathChanged));
//
//		public static void SetCommandPath(DependencyObject obj, string propertyValue)
//		{
//			obj.SetValue(CommandPathProperty, propertyValue);
//		}
//
//		public static string GetCommandPath(DependencyObject obj)
//		{
//			return (string)obj.GetValue(CommandPathProperty);
//		}
//
//		static void HandleCommandPathChanged(
//			DependencyObject d, DependencyPropertyChangedEventArgs e)
//		{
//			UIElement element = d as UIElement;
//			if (element == null)
//			{
//				return;
//			}
//			string commandName = e.NewValue != null ? e.NewValue.ToString() : null;
//			FrameworkElement ancestorElement = VisualTree.GetAncestorOrSelf<FrameworkElement>(element);
//			ResolveAndSetCommand(d, ancestorElement, commandName);
//		}
//
//		#endregion
//
//		static void ResolveAndSetCommand(
//			DependencyObject target, FrameworkElement source, string commandName)
//		{
//			object dataContext = source.DataContext;
//			if (dataContext == null)
//			{
//				/* In SL5 maybe handle data context changed. */
//				return;
//			}
//
//			if (string.IsNullOrWhiteSpace(commandName))
//			{
//				target.ClearValue(CommandProperty);
//			}
//
//			PropertyInfo propertyInfo = dataContext.GetType().GetProperty(commandName);
//			if (propertyInfo == null)
//			{
//				return;
//			}
//			object propertyValue = propertyInfo.GetValue(dataContext, new object[] { });
//			ICommand command = propertyValue as ICommand;
//			if (command == null)
//			{
//				target.ClearValue(CommandProperty);
//				return;
//			}
//
//			target.SetValue(CommandProperty, command);
//		}
//		#region DataContextProvider Property
//
//		public static DependencyProperty DataContextProviderProperty
//			= DependencyProperty.RegisterAttached(
//				"DataContextProvider",
//				typeof(FrameworkElement),
//				typeof(Commanding),
//				new PropertyMetadata(HandleDataContextProviderChanged));
//
//		public static void SetDataContextProvider(DependencyObject obj, FrameworkElement propertyValue)
//		{
//			obj.SetValue(DataContextProviderProperty, propertyValue);
//		}
//
//		public static FrameworkElement GetDataContextProvider(DependencyObject obj)
//		{
//			return (FrameworkElement)obj.GetValue(DataContextProviderProperty);
//		}
//
//		static void HandleDataContextProviderChanged(
//			DependencyObject d, DependencyPropertyChangedEventArgs e)
//		{
//			FrameworkElement element = e.NewValue as FrameworkElement;
//			if (element == null)
//			{
//				return;
//			}
//
//			d.Dispatcher.BeginInvoke(
//				delegate
//			        {
//			        	string commandName = GetCommandPath(d);
//						if (commandName == null)
//						{
//							return;
//						}
//						ResolveAndSetCommand(d, element, commandName);                       		
//			        });
//		}
//
//		#endregion
//#endif
	}
}